SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ab0a781f909535b90b82b05b70d58254cd94470c26369b317448218955ed6ba5' 
  AND token = 'm8hE4j8I81KJD9IRKo46a3sR+zaYRaqIFqZc7lXwrXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}